American Society of Hirudotherapy

Executive Summary: Antithrombotic Therapy for VTE Disease: Second Update of the CHEST Guideline and Expert Panel Report

Research article published in Chest (2021)

Last Updated: June 18, 2026Reviewed by: ASH Editorial Board
Research article — evidence reviewArticle reference
Evidence: Practice guidelineClinical TrialsStevens et al. · Chest, 2021

Abstract

BACKGROUND: This is the 2nd update to the 9th edition of these guidelines. We provide recommendations on 17 PICO (Population, Intervention, Comparator, Outcome) questions, four of which have not been addressed previously. METHODS: We generate strong and weak recommendations based on high-, moderate-, and low-certainty evidence, using GRADE (Grading of Recommendations, Assessment, Development, and Evaluation) methodology. RESULTS: The panel generated 29 guidance statements, 13 of which are graded as strong recommendations, covering aspects of antithrombotic management of VTE from initial management through secondary prevention and risk reduction of postthrombotic syndrome. Four new guidance statements have been added that did not appear in the 9th edition (2012) or 1st update (2016). Eight statements have been substantially modified from the 1st update. CONCLUSION: New evidence has emerged since 2016 that further informs the standard of care for patients with VTE. Substantial uncertainty remains regarding important management questions, particularly in limited disease and special patient populations.

Abstract sourced from PubMed (NCBI) for the cited record. See the original publication for the authoritative version.

Publication typeJournal ArticlePractice GuidelineResearch Support, Non-U.S. Gov't
Indexed MeSH termsDrug Therapy, CombinationEvidence-Based MedicineFibrinolytic AgentsFondaparinuxHeparin, Low-Molecular-WeightHumansInjections, IntravenousInjections, SubcutaneousInternational Normalized RatioPulmonary EmbolismRisk AssessmentThrombolytic Therapy

Summary

Peer-reviewed clinical and outcomes research relevant to medicinal leech therapy and its biology. Indexed in PubMed and verified against the NCBI record.

Why This Matters for Hirudotherapy

This executive summary of the second update to the 9th-edition CHEST guideline used GRADE methodology to address 17 PICO questions and issued 29 guidance statements (13 strong recommendations) spanning initial management, secondary prevention, and reduction of post-thrombotic syndrome in VTE. It matters to ASH as the authoritative standard-of-care reference framing how venous thromboembolism is actually treated, the clinical backdrop against which the antithrombotic rationale for the medicinal-leech secretome is positioned. This is a guideline/expert-panel document that synthesizes existing evidence rather than generating new data, makes no mention of hirudotherapy or leech-derived agents, and itself acknowledges substantial residual uncertainty in limited disease and special populations.

Citation

Executive Summary: Antithrombotic Therapy for VTE Disease: Second Update of the CHEST Guideline and Expert Panel Report.

Stevens et al. · Chest, 2021

DOI

Added to ASH library: May 28, 2026 · Site last updated: June 18, 2026

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